You can do as you wish....
If you found an experienced ferrari or exotic car mechanic you can certainly buy the maserati clutch parts or F1 Pump from the dealer and have them install them without voiding the warranty.
I recommend dealing with Kevin on this board. I ordered some parts from him and everything was great. He is a nice person to deal with and I bet he can give you a better deal on all the OEM parts than the dealer will.
I always try to plan ahead and I contacted two exotic mechanics in New Jersey and asked them about doing a Maserati clutch. Both claimed to be able, and both quoted me $3,000. To be honest, for $3,500 I will take it to the dealer. The $500.00 is peace of mind.
Same thing with the F1 pump, however when mine eventually goes after the warranty expires I will pay the $2,000-3,000 to the dealer. Again, the F1 pump is very "Maserati"... I think the dealer should do that and clutches.
Regarding the other services and oil changes, 12.5K, 18K etc. You can save a lot of cash just by buying the oil filter and the oil and going to a good mechanic. If the dealer charges you $350.00, Parts for an oil change will cost you $100.00 and maybe $100 more for labor depending on your mechanic.
Same thing with the services, save the plugs... You can buy all the OEM filters and fluids and have them changed. To see what I am talking about check out the service threads. Standard dealer labor rates are $100.00- 125.00 an hour and it seems like all the services invlove 10 hours or so... I am not anti dealer for Maserati specific service. But $50.00 for wiper fluid or 10 hours to replace an air filter at 12,000 miles..... I think a good mechanic can accomplish the same thing.
Good luck. Try to post your sevice costs on that thread so we all know what the going rates are.
CM