Great question… From most accounts, injections seem to work better than Muse. I have to tell you though, that if you worry about Peyronie’s disease, like I do, there is a danger where injections may produce scarring and therefore contribute to Peyronie’s.
I have had good success with Muse by following the instructions in the package to the letter.
Ask the doc to give you some samples. You may wish to start with 500mg. I don't think 250mg is worth it, unless your ED problem is minor anyway. You likely will not gain much benefit from 250mg. There are 750mg and 1000mg doses. For me, the 1000mg is a little too potent. Muse contains the same drug as many injections contain.
If you are very patient and follow the instructions to the letter, you may not get the side-effects such as burning in the urethra, that some report. I have no problems with it at all and would make use of it again.