From other peoples experiences with leccy pumps on early Tdm's, they tend to cause problems later on like leaking carbs and petrol pissing out of the over flow pipes constantly. They dont need a lot of pressure, in fact, they dont need any until your tank gets to about half full. Too strong a pressure and the needle valves cant close properly. I'd try and fix the original vacuum pump or go for the lower pressure pump, but then again its a trial and error jobbie. As an aside, on early Africa Twins, a popular upgrade is to replace the electric pump for a vacuum one. They reckon is more reliable.( than the standard AT one at least)
The one advantage I can see with an electric pump is that you can prime the carbs if you run out of petrol and avoid having to give your bike a blow-job.