Question Best HBB for a classic car

So we moved from MN to FL recently and DH has a classic car that all 3 of my kids adore! In MN of course it was only driven in the few warm months, but here it could potentially be driven all year. It's a convertible car too. We have 86 Y harnesses for my boys. They are 9 and 7. My 9 year old normally rides in an Amp in our Ody and the 7. 5 year old is just about ready to outgrow the HB part of a TB and I'm going to pick him up an Amp this week at Target as they are on sale. They use to ride in GN's in HB mode in the old car, but my oldest had just about outgrown that and I had 2 friends in need and gave them away before we left for FL. The classic car is coming down to FL this summer, so I've got some months to think about this, but what HB's would you consider? I of course need something that will last height wise, my boys are pretty average height. I'm debating between Probooster and SGL, wouldn't mind using them in our Ody at some point if needed and as far as I know pretty much all HB boosters suck in the 3rd row of our van except the HB TB.
I want something that will last, has great head protection and will be compatible with the 86 Y. Thanks!