Vista - Which is the maximum length for HDMI cable?

Cable length
The HDMI specification does not define a maximum cable length, but because of signal attenuation there is an upper limit to how long HDMI cables can be made.[44] The length of the HDMI cable made depends on the construction quality and materials that were used.[44] The signal attenuation and intersymbol interference which is caused by long cables can be compensated by using adaptive equalization.

HDMI 1.3 has defined two categories of cables: Category 1 certified cables which have been tested at 74.5 MHz (1080i/720p) and Category 2 certified cables which have been tested at 340 MHz (1600p) to reduce the confusion about which cables support which video formats.[45] A Category 1 HDMI cable will be marketed as a "Standard HDMI cable" and a Category 2 HDMI cable will be marketed as a "High Speed HDMI cable".[1] This labeling guideline for HDMI cables went into effect on October 17, 2008.[46][47] Category 1 and 2 cables can either meet the required parameter specifications for inter-pair skew, far-end crosstalk, attenuation, and differential impedance or they can meet the required non-equalized/equalized eye diagram requirements.[45] A cheaply made cable of about 5 meters (16 ft) can be manufactured to Category 1 specifications using 28 AWG conductors.[44] With better quality construction and materials (24 AWG conductors) an HDMI cable can reach lengths of up to 15 meters (49 ft).[44] The HDMI website has stated that many HDMI cables under 5 meters of length that were made before the HDMI 1.3 specification can work as a Category 2 cable but cautions that only Category 2 tested cables are guaranteed to work.[48] Long cable lengths can cause instability of HDCP and blinking on the screen due to the weakened DDC signal which HDCP requires. HDCP DDC signals must be multiplexed with TMDS video signals to be compliant with HDCP requirements for HDMI extenders based on a single Category 5/Category 6 cable.[49][50] Several companies offer amplifiers, equalizers, and repeaters that can string several standard HDMI cables together. Active HDMI cables use electronics within

Hi panais, 50,000:1 is very impressive!

50ft is not long at all, if 500ft then you may think of the signal quality.

All HDMI cables should have the same pin out. I don't see any variations yet.
Unlike S-Video cables which has different number of pins for different equipments.

As far as quality goes, for cable, usually the more expensive ones are built with better looking connector. There are no different between a $500 and a$50 one; they work the same as far as for human observation.

As for the examples below, I believe the quality are the same built with nice thick cable and gold connectors. Have you consider drill hole through the wall for using shorter cable.

Amazon.com: 50ft HDMI to HDMI Premium Gold Series Cable w/Gold Plated Connectors ATC Certifi: Electronics

Amazon.com: Monster HDMI 1000HD Ultra-High Speed HDMI Cable (50 Ft.): Electronics