It's been too long since I've played Shadowrun; how fast are the fights? I like fast fights in general, and wonder if 4e D&D/Shadowrun is a good candidate for raising monster damage / lowering monster hit points. The minion concept definitely is awesome for this game. Getting chased across an apartment block by literally dozens of soldiers is pretty damn invigorating.
I'll comment since I'm actually playing the latest edition of Shadowrun on a regular basis. (We basically have about 5 six-hour sessions of different DMs/campaigns every month, and Shadowrun is in regular rotation.)
The speed of combat resolution varies.
Due to the number of dice required to roll ("16 dice of lightning bolt on that sucka!") and the number of situational variables to track ("OK I'll roll 12 dice for dodge and body and armor to determine the number of wounds he takes, while you roll 6 dice for drain") it's technically a long drawn out affair.
But because combat modifiers are usually straightforward (no saving throws, immediate interrupts), all you really need is for players to really know what they're doing at any given turn, and for a GM to be really good at adjudicating things on the fly and with confidence.
Our GM 'complains' that fights are sooo long in Shadowrun, but as someone who GMs at the 4th Ed table, I'd say that they're equally long especially when players are basically trying to exhaust their action economy every round by poring over their character sheet 10 minutes at a time.
Granted, the matters at both tables can be modified by strict table rules, but in any case, my point is that given certain conditions, I think both Shadowrun and 4E are not so far from one another in terms of speed of play.