vp@1.1 vs Overgaming (bo1)
that just failed my express. I fancied VP to beat Navi (which they did after a shaky start; loosing the first CT half 10-5) but I'd expect them to beat over gaming - especially after starting on CT.

Having losing the first CT half @ 4:11 the game was already over at half-time.
Unfortunately, this is one of those 'freak-of-the-moment' type bets that happens in bo1 matches. Ideally, you would only ever bet BIG on 'bo3' formats to counter-this, but with 90% of csgo matches being bo1 this is not always practical.

People will tell you to avoid 90-10 matches where the returns are ONLY @1.1, I disagree. they can be very useful to add to your express order to 'BOOST' your returns for example:
WITH 90-10 matches added to your express:
HR@1.1 vsA-gaming (bo1)
LDLC@1.1 vs orbit (bo1)
LDLC@1.04 vs A-gaming (bo1)
navi@1.1 vs 3dmax (bo1)
navi@ 1.1 vs mtw (bo3)
nip@1.04 vs thelonerangers (bo1)
Nip@1.7 vs LDLC (bo1) <------ (note: this is your 'gambling' match)
returns: $5 x 3.00 = $15

WITHOUT 90-10 matches added to your express:
Nip@1.7 vs LDLC (bo1) <------ (note: this is your 'gambling' match)
returns: $5 x 1.7 = $8.5

as you can see when you add 90% safe matches to your express you almost double you're returns for very little added risk.

If you wan't a 'gamble free' approach you can still go high on the heavy favourites provided it is a 'bo3' series. The risk will be minimal and you're returns will be minimal, but so long as you keep winning small amounts - you will have a steady stream of income which can be used to gamble with (potentially multiplying returns, again and again and again)