For a long time now I have processed my own black and white film, starting in the Imperial College darkroom (where I also did some C41 and E6), and continuing to this day. It is rewarding to process oneself but I must say my main motivation is really the cost. A process and high quality scan will run me around £14 if I decide to mail it in to Peak Imaging which soon adds up if I shoot a number of rolls and so its clear to see why I often choose to do it myself. This comes with some significant compromises: I don't have a great washing / drying process for the negative and my self developed rolls do end up with watermarks and dust (and I'm very thankful for the Lightroom heal brush!).
For self scanning I have owned an Epson v500 now for around 4 years and it has served me relatively well for both 35mm and medium format. Its pretty affordable and perhaps cost me £100 second hand on eBay in 2013. For the cost the scanner is really good in my opinion, particularly for B&W medium format as you can see from the examples below.
The top image was drum scanned by Peak Imaging using their Archive service. To be clear I think their service is very good and the quality of the scans are fantastic but the second I processed and scanned myself with the v500 and small sizes it is no slouch.
For 35mm film the example below should and does illustrate a larger gulf in quality. The top is drum scanned and the bottom I did myself. You may of may not like the amount of sharpening applied in the top one, I personally prefer it, as I do with the colours in the drum scanned version. The vibrancy and analogue gradient between colours I find much more pleasing in the lab scanned image, particularly as the sun is breaking through the mountains of Rio in this shot.
So overall no big surprises - you get what you pay for. For me as a hobbyist it is hard to justify the cost of a pro lab dev and scan for every roll and so I find the self scanning on the v500 a huge help. But when I have a special roll from a once in a lifetime trip I have no remorse paying for the pros to get me the best out of my film.