They're all pretty much the same and the majority of the in-tank pumps for our cars are made by Walbro regardless of the brand that's stamped on it.
The low pressure variety is all you need for pretty much any application that does not include the use of an FMU. The high pressure variant does provide a couple more L/Hr but they really shine at elevated fuel pressures because they're a bit more resistant to loosing volume to back-pressure.
I've got a Walbro 255lph on my car and I love it. It's an inline pump on my '73. Good thing about a 255lph is...you really should never have to upgrade again.
Go to Ebay, and search TRE Performance. They have their own pump, and its quieter and cheaper than the Walbro. I just installed one on my 93 Cobra and it works great.