Yeah I hear you. When it comes to creating sound files from scratch I haven't had the time to go down that particular rabbit hole!
But there are other reasons I strongly recommend the Lokprogrammer... Blank decoders can be got for 99euro from supplies like Modellbahne. The cheapest decoders I can find from the UK (with a loaded soundfile) cost around £115 and if for some reason you're not happy with the file, you're stuck with it! (I realise suppliers are accommodating and will probably change a file for you but that necessitates you sending the decoder back to them). Legomanbiffo, who uses Loksound, will sell you the file if you wish for £10 so you can load and fine tune it yourself.
Also, ESU are constantly upgrading the firmware and features on the V4 decoders. Full Throttle, for example, needed a firmware update for it to function, the improved brake function is the same. Without the programmer I'd have had to send my decoders off to be reblown before I could use those features.