A form 1 is the only way to “make” and NFA item like and SBR.
The only other option is to buy a factory SBR or SBR lower which you would obtain via a form 4.
The only real difference is if you “make” and SBR by registering your lower once the tax stamp is approved you must engrave the lower with the “Makers” name, city and state. Obviously this make your SBR less attractive if you ever tried to resell it.
The last time e forms was availible it was faster than paper but at that time trust transactions did not require fingerprints and photos so it’s hard to say if that wil still be the case. Apparently the FBI fingerprint check is a bottleneck.