Personal choice, but I run my paper logbook in parallel to MCC Pilotlog, which is an absolutely superb piece of software.
All the questions you raise are well answered in the help files and FAQs and you will probably get a more thorough answer by reading those than anything I can jot down here.
Suffice to say that there are a number of ways of incorporating previous flying experience into MCC. The logbook can be presented and printed in virtually all the main logbook formats and what I can generate on screen matches exactly what is written in my paper logbook (which makes totalling up columns a doddle).
There are companion apps for iOS, Android etc, which will sync automatically with the desktop version.
Support is excellent, the features are superb and it has saved me hours (probably days) with number crunching the stats. I've flown several different classes of aircraft under a few different regulatory regimes, and when job application forms and CAA forms required breakdowns of experience, it would often take a whole afternoon to work it out the old fashioned way - MCC will spit out the result instantly.
Can't recommend it enough!
