The reason for the lack of guides is that it's only recently become possible to make an AR/TA (or a TA/AR defender for that matter).
I haven't played AR/TA but I have played both those sets so overall I'd say it's an ok pairing. AR is a VERY good AoE damage set and TA is an ok buff set with several -res debuffs. So overall you're going to toss out a LOT of very good AoE damage.
The main downsides are alpha-mitigation and redraw. TA is not a great set for mitigating the alpha-strike, it's got ok mitigation overall but not in the types that mitigate alpha-strike damage (it relies a lot on slow and knockdown). Redraw is also potentially an issue since you're redrawing when going in both directions. The upside is that TA works reasonably well if you set out your debuffs first and then switch to blasting.
This is probably the best TA guide out there:
http://boards.cityofheroes.com/showthread.php?t=122243
I'm less sure about AR guides but in my opinion it basically comes down to: take Burst, Slug, Buckshot, Ignite (if you solo a lot and have a mez to hold enemies in position), Flamethrower and Full Auto. Fit M30, Sniper Rifle and Beanbag in if you can and if they fit your style (of those three I'd probably only take M30 on an AR/TA, Sniper Rifle costs you the element of surprise for laying down debuffs and TA has several holds already which limits the usefulness of a ST stun).
Thanks for the info
Are there any guides out there for this AT ? Searched through most of the guides and have not found any ? Is this a bad mix of powers ? Just wondering , thanks .