Studio Slips Clam Shell Gig Bag - T3

I know a few of you have purchased the Studio Slips Clam Shell Gig Bags (double padded) and I’m considering the same.
Is this essentially just a big bag or do they actually have some sort of base whereby the T3 can sit thus limiting side-to-side movement.
Also, is there any kind of handle for lifting? I have their Clam Shells for my guitar amps so I am familiar with the construction.

Thanks,