Backin' Up, Backin' Up... Well, Cuttin' Back, Anyway...

In an insanely strong effort to reduce the amount of money I burn every month, I've recently been considering switching to a "pay-as-as-you-go" model for my cellular phone use. Currently, I am a T-Mobile customer. They have been my only phone company since ditching the land-line cords when I was 19. Strange to think that I've been with them for so long, seeing as the reception, though slowly improving over the years has never been that great. However, I stuck by them because of their customer service skills. I have never been dissatisfied with any of their performance except for the odd dropped call. Over the years, I have had, maybe three different plans. Now, seeing as I text more than talk, I find it a bit silly to pay almost $60.00 a month for some minutes I don't need and processing costs. My plan, which I had them add unlimited texting to for $15.00 a month, before taxes/surcharges/blah blah blah, is actually only a $35.00 plan. So, after texting, I am still paying $10.00 a month just to have a plan.
Dumb.
Any of you ever have a "pay-as-you-go" phone/plan? Pros? Cons? What company did you use? What were their pros and cons? After a little, light research, I've discovered a company called Earth Tones. They have relatively decent plans, a few okay phones and they donate 100% of their profits to environmental causes! That last one is the clincher for me, really. Because, honestly, I'm tired of all of the whistles and bells on my cell. I waste my time enough without screwing around with that thing, too! :P Also, I think that a "p-a-y-g" plan could be good for me. It will limit my monthly bill spending, keep me from buying ringtones or games that aren't even transferable (which I haven't actually done since last Halloween...) and it will give me an excuse to cut conversations short because I really dislike talking on the phone. "Sorry, I can't use up too many minutes, can we text or meet and chat?" Perfect!
It looks like I've gone between 150 and 180 minutes in the last three billing cycles, with one of them only 50 minutes! Of course, the texts are usually around 150 to 200 a month. But that's alright. That's what text plans are for. Anyway, Earth Tones has a few "plans" that could suit me.
200 Anywhere/Anytime minutes is $25.00. 400 minutes would be $35.00. Of course, I'll need to add a text plan onto that. For $5.00, I can have 200 texts available to me. Since I have been sending and receiving over 200, the next plan up would be the way to go at $10.00 for 500 texts. 500! I'll have to look into it further, but if they don't have surcharges and all of that other crap, I could have a way better plan for $10-$15.00 less than what I pay now. And their coverage map actually looks pretty impressive. So, we'll see.
Just so everyone knows, this has not become an ad blog. I'm not getting paid or even asked to mention any of these companies or causes. I am simply mentioning businesses and causes I think are worth mentioning and helping out.
Anyway, again, if any of you have had pay-as-you-go plans, please chime in with your experiences and recommendations. I'd be ever so grateful!
Thanks pallies!