welcome to srp.

since it's in your budget, i'd definitely recommend the feather over the standard razors with disposable blades. its' a whole lot better made razor and at least for me that translated in better function.
i didn't have any issues with the sharpness of the blades, but i suppose it depends on your dextresity.

regular straight razors are different enough from the feather. usually they aren't as sharp, the blades are longer and could be a lot more flexible than a feather. a good brands are dovo, thiers issard, or boker. you probably want to get it not from jermin street but from one of the online vendors who can ensure the razor has a good edge. a 5/8 to 6/8 is good to get and i think there's just one dovo model with very heavy horn scales that i'd avoid (and i the scales on the micarta one are a bit on the heavy side, but fairly manageable).