Strange, I typed a response, had it show up, but then after going back to the sites home page it vanished.
Couldn't be bothered typing the entire response again (on a tablet at the moment), but the short of it is that any new storage device, be it a slower solid state device like an sdcard or cf card, or a standard sata drive will be capable of more than the fastest ide/SCSI controller available for classic Amigas. That being said if storage space per buck is important to you, you may as well just get a standard sata hard drive plus SCSI adaptor. Speed will be much the same as a fast ssd on an Amiga, but its considerably cheaper per GB (and before anyone with a compulsion to state the obvious feels the urge to point out that solid state storage can be cheap these days I'm speaking in relative terms).