No, cheap HDMI cables should offer the same performance as expensive cables. Performance and quality are not the same thing.
A quality product is able to maintain performance over time. The quality product doesn't have connectors that get too loose as you use them again and again, doesn't stop working after a couple of months, doesn't have the connector head break away from the cable, etc. Cheap cables can be quality cables, but it's not wise to assume that all cheap cables are created equally.
As far as the adapters go, a person can read the reviews on Amazon for the OEM HTC adapter and the generic adapter linked above, compare the reviews and decide for himself which will best meet his needs. The performance seems to be the same, but the quality is not.