You should be able to reqesut an upgrade from the QS1 MC to a regular QS MC with no annual fee and same reward structure. Everything I've read on hear says it's nearly impossible to PC from the MC to the Visa. There were a couple instances I read but they went through multpile product changes to eventually get there.
There's lots of info around here on QS1 to QS upgrades... here's the general 'gist' of it:
- It's true that you can't change from MasterCard to Visa (or vice versa). However, you can upgrade a QS1 MasterCard to a QS MasterCard. The only difference here is the AF; the QS1 has has an AF, the QS does not. The rewards are identical on QS1 and QS cards.
- The upgrade is offered almost immediately for some people, while others (like myself) went for years hearing "there is no offer on the account" only to one day have an offer 'miraculously' appear. It's truly YMMV.
- Some people feel the CLIs are more generous on the Visa version compared to the MasterCard, but this hasn't been my personal experience. I have both (Visa and MasterCard) Quicksilver cards, and the last couple of times I've used the "button" I've received identical CLIs on each card. FWIW I don't use either very often, so that likely 'stunts' my increases somewhat.
With Capital One you can pretty much go from any 'flavor' card to another as long as an "offer" is available. Also, once you accept an offer/upgrade/change, you can't change again for six months (usually not a problem for most people). Actually, the only combination I've ever not seen is a Quicksilver One Visa, which just (generally) wouldn't make sense. That being said, there's probably someone who has one due to some weird one-off situation.
Hope this helps! 
Edited to clarify: I've never seen anybody on here get an account changed from one network to another with Capital One (i.e. MasterCard to Visa), not even with the EO. However I have read of this being done with BoA accounts.
@Anonymous wrote:
I have a Quicksilver One Visa which was a PC from a Visa Platinum. The original card was with HSBC before Cap 1 took over though.
LOL... I knew there would be one around here somewhere! 
Hit them up for an upgrade... you're likely in the same situation I was in until they finally upgraded my old card. Of course if you have a permanent fee waiver, there's no reason to bother.
(My QS MasterCard was also Orchard/HSBC)
@UncleB wrote:
@Anonymous wrote:
I have a Quicksilver One Visa which was a PC from a Visa Platinum. The original card was with HSBC before Cap 1 took over though.LOL... I knew there would be one around here somewhere!
Hit them up for an upgrade... you're likely in the same situation I was in until they finally upgraded my old card. Of course if you have a permanent fee waiver, there's no reason to bother.
(My QS MasterCard was also Orchard/HSBC)
I plan to check for an upgrade soon 