Don't know how similar these are to the Radical, but I recently got to spend some time with two very different but both outstanding larger frames. The Kneissl Black Star is a beauty. It does every thing well, feels incredible and you really have no idea it's a 100+ frame. Fantastic stick from this company. They might be a little hard to find, but if you get a chance, I'd say take one out for spin.
I also hit with the old PK 5G Kinetic. In the past I've played around with other models and was always impressed with the Kinetic technology and this one was no exception. Again - I think it was around 100" but you'd never think it except you never miss the sweetspot. The frame directs shots easily, spin is good and despite being relatively stiff, the feel is also very very good. It really gives you the benefits of a stiff frame without losing the comfort of a softer one. Very impressed.
Of the two, I would guess the Kneissl is probably closer in feel to the Radical as it's a more traditional type beast. The PK is really quite unique - but I found them both exceptional.