I think a lot of people view these frames through rose-tinted glasses as they represent a cool part of trials history, but realistically they were the best of a somewhat bad bunch. As you mentioned, they developed a reputation for cracking - as you're buying second hand, it's hard to know what that frame has been through so far so it's hard to say how long it'll last. The frame is the most expensive thing to have to replace, so with a bit of a question mark hanging over that I'd be a little concerned.
That Hope Bulb hub probably won't feel great compared to your FFW setup (EDIT: Just did a quick check, from memory they had low 20's engagement points but it turns out they're 36 click so not too bad), and if you have any issues it's only going to get harder to solve them with that hub no longer being supported by Hope. If you do need to replace that, that's also a decent chunk of money to switch out. If you decided to do a complete wheel, I think you'll also be limited on rim choice as I would imagine that frame will have comparatively narrow brake mount spacing.
If that front brake hasn't been used for a while and is a similar vintage to the other parts, you may find that things like the seals won't really work super well and may need to be replaced. Again, if it's an older model that's no longer supported then getting spares might be problematic.
If you can get a good price for the bike it may be worth it just to scratch that itch, but it's just worth going into it with your eyes open. More modern bikes will tend to have fewer constraints on what you can/can't replace, and will most likely have more support available for parts fitted to them. Breaking parts on them is less likely to cascade from "I think I need a $5 part" to "I need to spend $200 on X, Y and Z". When I worked at TartyBikes it was really common to see people get in touch having bought a cheap, second hand bike expecting it to be a quick and easy bike to freshen up only to find that costs quickly ramped up. With how much part costs have jumped and how much part availability has dropped, that's only really become worse in many ways.
Sorry for being a downer about it - as I said, if you can get it for what feels like a good price to you then it may be a good option to see if you really want or need that style of bike in your life.
That Hope Bulb hub probably won't feel great compared to your FFW setup (EDIT: Just did a quick check, from memory they had low 20's engagement points but it turns out they're 36 click so not too bad), and if you have any issues it's only going to get harder to solve them with that hub no longer being supported by Hope. If you do need to replace that, that's also a decent chunk of money to switch out. If you decided to do a complete wheel, I think you'll also be limited on rim choice as I would imagine that frame will have comparatively narrow brake mount spacing.
If that front brake hasn't been used for a while and is a similar vintage to the other parts, you may find that things like the seals won't really work super well and may need to be replaced. Again, if it's an older model that's no longer supported then getting spares might be problematic.
If you can get a good price for the bike it may be worth it just to scratch that itch, but it's just worth going into it with your eyes open. More modern bikes will tend to have fewer constraints on what you can/can't replace, and will most likely have more support available for parts fitted to them. Breaking parts on them is less likely to cascade from "I think I need a $5 part" to "I need to spend $200 on X, Y and Z". When I worked at TartyBikes it was really common to see people get in touch having bought a cheap, second hand bike expecting it to be a quick and easy bike to freshen up only to find that costs quickly ramped up. With how much part costs have jumped and how much part availability has dropped, that's only really become worse in many ways.
Sorry for being a downer about it - as I said, if you can get it for what feels like a good price to you then it may be a good option to see if you really want or need that style of bike in your life.
