Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
Ability to post and comment on topics and discussions.
A Free photo gallery to share your dive photos with the world.
Either one will work just fine. What you need to ask yourself is what is important: price, cosmetic, dive environment, future goals. For example, tech divers lean toward the G260 because some are taught to remove the front cover to clear debris. In cold water, below 40°F, the G260 works very well, although I've know the S620Ti does just fine too. For some, one second stage looks more appealing than the other. Flip a coin if you can't decide.
I have both and either one is fine...the 620 is slightly lighter....I use the 260 as my primary and necklace the 620ti...I could easily do it the other way....I also alternate the 420 as the primary with the 260...
Go with whichever you get the best deal on, the 260 is usually cheaper and offers some advantages like reversible inlet, if they were the same cost it wold be tough to decide but ultimately I consider the G260 the best in-line type reg SP offers. The 620 is no slouch.