Going on my own experience, you're better with powder rather than tablets.
The tablets are for the average Joe who will take one a day for the immune boosting, improved digestion effects you get from L-Glutamine.
If you are taking it for bodybuilding purposes I'd say about 5g before you train will be fine, some folks take up to 10g a day. (That's 20 tablets!).
So, it gets expensive even at half price costs, as well as being a pain in the ass to take 10 to 20 tablets.
The cheapest place I've seen is online at woods pharmacy.
Regarding L or not L, I don't think it matters as it's the same stuff you buy.
http://www.supplemen****ch.com/supat...s.asp?letter=G
This website is great for unbiased info on Supplements. Incidentally, the missing letters in the web address are "t-w-a-t" I kid you not. Is that why they've been blanked out?.