I just started the CGMS a couple months ago and I like it, with a few caveats. But you're not going to "swap", unless you mean you're going to upgrade to the CGMS-compatible pump. The pump looks and acts exactly the same. Once you get the sensors, they'll teach you how to put them in. You will have to insert it into a different spot within a few inches of your pump for best data transmission. The whole sensor/site is only about 2"x1", and you can cover it with a Band-Aid or Tegaderm if you want to secure it. You can keep it in for 6 days, some do it even longer.
So far my issues with it are that it is not very accurate at the high and low levels, so I wouldn't count on it to alert you if you go low. It's a common issue that they're still working on. Also, the fact that it takes up another site and that it has to be close to the pump site but not too close is challenging...there's only so much acreage on my abdomen to go around! The other thing is that you have to calibrate it a few times a day to make it better agree with your actual BG's, but there are specific restrictions on when you can do that so it takes some planning. The CGMS doesn't replace BG meter checks, in fact you may end up doing more. It's mainly good for looking at trends over several hour periods, such as what does your BG do overnight or after you eat fatty foods. If your insurance covers it, I'd go for it, but it's got a long way to go before it's really useful.
Type 1 for 25 years