I have a Tabou manta that I now very rarely use (98 l for 93 kg..



) but my son blasts around the choppy bay on it like if it was a lake...
Compared to an allride it'll be night and day, at first you probably won't handle the chop as you're used too..especially downwind !!

But speed wise it will be a huge improvement, I would recommend you try a slalom board first, whatever the make, cause they only have "outside" positions for the straps, can be disturbing if you're not easy with that type of sailing.
Those boards you mention are quite technical to ride and need good fins to get them going (sold without fins).
Depending on your level you could also settle for the freerace editions of those boards,more "accessible" : an inside strap position, no carbon (so not as stiff) and delivered with a fin ! for example : the speedster instead of the manta (it's a beauty !!) the futura instead of the isonic.