Looks like Kroger's Sprint-based iWireless brand is upping the ante a bit on features, making them a viable alternative to one of the mainline carriers (Virgin Mobile comes to mind) for certain applications...
First off, their phone lineup has improved, and all phones now come with $50 in airtime built in, a very nice amount to start off with so you can take full advantage of all the service's features right out of the box, no refill required. The phone pricing actually isn't that bad when you count the $50 in included airtime into the equation, and the variety is better than your typical Sprint-based prepaid:
LG 145 (aka LG 200c on Tracfone) - $50
LG 160 (almost aka Flare on Virgin Mobile) - $70
LG 150 - $80
UTStarCom 7025 - $50
Sanyo Katana II - $120
LG Rumor (finally a nice texting phone on prepaid for a decent price!) - $150
Before you mention it, yes, Kajeet also has the LG Rumor, but at $100 for the phone alone (plus $50 for the included airtime) this deal is a lot better. Plus there's a plan to use it: $19.99 per month gets you unlimited text messaging. Not as good as Virgin Mobile maybe, where $19.99 or even $10 (depending on your plan) gets unlimited messaging of all types, but iWireless' phone is better for the price, with an mp3 player, memory card slot and a non-Kyocera brand name.
iWireless has also redone their rate structure. All refills last 90 days, but that's not the big part....here's the rundown, cheapest per month to most expensive:
1. 25 cent daytime minute with 10 cent nights and weekends starting at 6 p.m. (not a misprint, nights are 6 p.m. on iWireless!)
2. 15 cent anytime minutes, 10 cents per minute extra to Mexico
3. $4.99 per month plus 10 cent anytime minutes
4. $29.99 per month for unlimited nights and weekends starting at 6 p.m. (!), 10 cent minutes at other times
A quick analysis shows that if you use 100 minutes or more per month, the $5 a month plan is best. If you use mostly night and weekend minutes (2x or more as many as weekday minutes) the 25/10 plan is good up until 300 minutes per month. Or if you use 100 anytime minutes and 250 night and weekend minutes (or more) the $29.99 a month fee pays for itself. I like math ;)
EDITED: So, in short, you have a very good wireless service rate-wise with a few unique features (nights starting at 6 p.m.) and several decent phones to choose from (mostly LG) at a reasonable price. You can get them online (contrary to what I said before, thanks to offthegrid for correcting my egregious error) and the list of stores where they're available is rather large: King Sooper's, Kroger, Fry's (food, not electronics), Smith's, CItyMarket, Dillons, Ralphs, Food4Less, FredMeyer or QFC. Betcha the same company owns all of 'em.
But if you can, in many cases it's a better option than Virgin Mobile (free incoming texts, nights starting at 6 p.m., better phones, cheaper 10-cent rate plan, cheaper per-minute rate plan) or STi Mobile (better phones, better night-and-weekend plan, etc.). I've already recommended the service to a friend who has Virgin, and he may very well switch, since a King Sooper's isn't too far away here in Colorado.