Billy, I think the main reason most people shy from them is the fact that 99% of them are placed prior to the throttle body. Doesn't sound like a problem until you think about it. Spraying the fuel before the intake runner means you have no control over which runner the fuel goes into. 90% of the time, these set-ups end up with every cylinder either running rich or lean. Thats why, in most cases, you no longer see factory or OEM replacement fuel systems using these set-ups
The optimum way to control your fuel (IMO) would be a full stand alone engine management. Cost and complexity are the most prohibitive problems on this one. Next I would say additional injectors placed in the Intake runners, with some kind of controller referencing RPM, and intake pressure. The problem here is there is a lot of fabrication involved and programing the controller can sometimes beharder than the Stand alone. After that, I would recommend a piggyback computer (like the Apex-i S-AFC or the Split Second MAF Conversion). Like Phil already ststed, the biggest limitsation here is that your not making a new map, your modifying the stock one. Last on my list would be a tie between the RRFPR and larger injectors with modifying the AFM. The RRFPR idea has always struck me as a band-aid, when a tournoquet is needed. The larger injectors and ther AFM mods, your never really able to get optimum tuning thru the entire RPM range...