Am I good candidate for upper arm lipo? Will it leave any sagging skin or irregularities?

You should have pretty good skin contractability at your age. Consequently, you should get a good result from liposuction. Skin removal (brachioplasty) would most probably not be needed and would leave potentially noticeable scars on your arms. I would not recommend a brachioplasty for this situation. This is an area, however, where it is important to be conservative in the treatment to avoid irregularities.For the best results seek the consultation of a plastic
surgeon certified by the American Board of Plastic Surgery. They have a website
listing all the certified plastic surgeons. Members of the American Society of
Aesthetic Plastic Surgery will all be board certified in plastic surgery and
have demonstrated an interest and competence in cosmetic plastic surgery as
well.

Arm liposuction is a procedure that depends upon skin elasticity to work.  First, it must we done with great care to avoid irregularities and nerve injuries.  Second, there must be restraint because an over resection is far worse than an under resection.  Finally, as you get older, your skin becomes less elastic, and you may wish for that fat to come pack to fill out the sagging.  Liposuction combined with skin resection (brachioplasty) can work well.