One easy way to provide a paid vs. ads system would be to streamline under a single business model.
One example would be a user generated content site that allowed users to "be their own advertiser", and pay in proportion to their traffic/clickthrough/CTA value.
Unfortunately, while this may be easier for you as a company/accountant/developer, users have indicated pretty clearly that metered billing is too damn confusing, for the most part. One possible way to alleviate this is to offer the site as free with ads, but advertise at an inverse rate to the user's "ad value" – thus, no one ever has to "pay in", but you still provide a cleaner/less disturbed experience for your highest-value users.
Come to think of it, plugging in a site visitor's Klout score/other reputation metric, and then turning off ads for people above a certain level of influence might even be a generally good idea, as it removes all distractions from your site/content/design from the people most likely to spread the word virally to the mainstream follow-on visitors you will actually monetize.
Since the British are secretly holding onto Michelle Obama's Scottish Birth Certificate, there was general agreement to just go low-key on the matter, and hope no one notices…
A lot of this depends on the thickness of the blade, and the hair it's cutting. In my experience, regardless of the tactics I use, I notice a significant difference in blade sharpness immediately after the first use if I've grow out my facial hair a bit. This is pretty consistent with the guys I know with thicker hair who use the same/similar cartridges. For finer hair, I'm sure the techniques Dev mentioned will work to increase blade lifespan, prevent rusting, etc.
It's very similar to having a set of professional chef's knives – it's MUCH easier to notice when they start to go dull from being freshly sharpened (0-25% dull), than to measure the loss in sharpness from then on (26-100% dull). In fact, someone unfamiliar with the knives may even think they still "cut just fine", without realizing how much arm strength they are putting into the cut, or how ragged the cut ends of their meats/veggies/etc are, compared with a fresh knife.
The real issue is that there are few effective means to resharpen newer disposables. I recall there being a product on the market that worked really well with dual-blade cartridges, but I haven't seen anything that works with 3-4 blades (which is what I use now).
I would tend to measure in terms of "shave weeks/blade". The main variables are the thickness/amount of hair to be cut, and the regrowth rate.
Personally, Mach 3 gives me 1 shave week/blade… Whether I shave daily, twice a week, or even just once, the amount and thickness of hair compensate to basically make any additional attempted use of the same cartridge a game of "how much would you like to bleed?"
Just to give you some baseline info, I usually feel a little hair coming back 8-10 hours after a shave, and downright fuzzy the next day. I usually go 2-3 days between, though, otherwise I have a hard time getting a GOOD shave that can grab/pull the hair the right way as it slices.
In my own experience, transitioning from "old school" dual blade razors and/or electrics, using the Gillette Mach 3 was a revelation in how much closer and smoother a shave I could get with little effort, and how fewer times I would tend to cut myself when shaving in a hurry.
I also had great luck using these same blades to shave my head bald.
Which is where things start to diverge a bit…
In more recent years, I've received test samples of the Quattro and whatever the 5-bladed monstrosity is called. For facial shave, the smoothness/ease of use did seem to increase incrementally by number of blades.
The cutting effectiveness, however, was reduced by one simple fact – the blade heads are only slightly bigger than their 3-bladed counterparts, which means thinner and/or more angled blades in each cartridge. For me, this meant the blades would dull much faster than with the Mach-3. Just to give you an idea, I usually pull about 1 week out of a blade (pretty coarse hair) doing just my face, or a single use between scalp and face (then it gets dull/nicked enough that subsequent uses turn me into a bloody mess).
Because of the sheer number of blades, the newer units also seem somewhat less "flexible", which also made using them to shave the top of my head basically impossible.
Overall, I find the 3-blade units are the best overall price-performance value for any type of shaving. If I was going to keep a separate set of blades for my scalp, I'd probably scale back to the "Sensor Excel", a dual blade unit, but use the "HeadBlade" to hold the cartridge (versus the standard "stick" style razor handle).
And if I had a lot of money kicking around, I'd probably then 'upgrade' my face razor to the Quattro or above (but at that stage, it might make more sense to just get a pro barber shave given the huge cost per cartridge).
To sum up: 2-3 blades allows you to cut more effectively without pressure/angling of the blades that may otherwise cause cuts… And 4-5 blades will certainly increase the feeling of "closeness", at least right after the shave.
I would expand on Dylan's answer, and suggest that buying such blades online will, in most cases, prove as cheap or cheaper than a similar purchase at the retailers/wholesalers mentioned.
That said, there are several "Costco multipliers" that people forget about:
- The cash back credit that accompanies the Executive level membership. If you buy enough high ticket items (razor blades definitely qualifying there), you can make back the membership price easily and get a nice check back at the end of the year.
- Usage of a Costco American Express, which increases the potential cash back amount over the course of a year.
- Time and resources (especially gas, these days) saved by buying in bulk, and reducing the total number of trips – Costco is the only one of the stores mentioned by the querent that I've never seen run out of Mach 3 blades, ever. I've yet to see blades rust or degrade prior to use, so it may be wise not to eliminate Costco as an option if nearby/you make regular trips.
Long story short, if you're a Costco executive member and/or Amex holder, it's probably a better deal to buy locally. If you are not, or do not have a convenient Costco, then purchasing from a tax-free source online is likely to yield a more consistently lower price.
As for an ordered list, the last time (~6 months ago) I checked, the pricing per blade was actually nearly identical across Safeway/Lucky/Walgreens/Costco.
As I said, Costco won out for me personally on different criteria (cash back), and sometimes the prices fluctuated up or down at the others (I've definitely seen the blades go on sale at Safeway, yielding a cheaper price by $1-2, but it's rare).