difference in quality of sensors?

Projects General Guidance
1

i recently purchased a compass module and laser distance module from ebay.
https://www.ebay.com/itm/VL53L0X-Laser-Time-of-Flight-Distance-Sensor-Module-for-Arduino-Purple/113532912331?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

https://www.ebay.com/itm/GY-273-HMC5883L-Triple-Axis-Compass-Magnetometer-Sensor-Module-For-Arduino3V-5VB/173810722501?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I am new to arduino. these sensors are working but seem VERY inaccurate.
the laser readings seem to bounce around quite a bit but after a half a mile of scripting and taking out spikes and using averages. i am getting exceptable readings.

i have now been working with the compass for several night and from all that i have read i have everything set up correctly. but the reading are SO bad that i cant see this module being usfull to anyone.

the reading on the compass have a bigger bounce than the laser and my averages read up to 20-30 degrees different when twisted back to the same spot.

so my question is.....

Does the accuracy and quality of modules differ depending on where they are manufactured?
has any one had any experience comparing "generic" modules with "real" modules?

is there something i should be looking for to make sure I am buying quality?

are there more accurate "high end" sensors available for distance and rotation?

2

taterking:
are there more accurate "high end" sensors available for distance and rotation?

For my Arduino RC plane I use a LiDAR Lite V3 distance sensor and a BNO055 IMU for orientation information (including rotation). Depending on the project, though, you could use an encoder to measure rotation.

3

Did you already try the Arduino libraries for these sensors?

In the future you can save much time if you only buy modules coming with data sheets and Arduino libraries and examples, and at least 2 each for comparison.

4

there most certainly are:

The Octans

Price tag: 1 ton dually diesel crew cab

5

i did find arduino libraries to work with them. i believe i purchased "clones" of the name brand modules.
I found data sheets online. I think i will take a recommendation from @Power_Broker and try the modules he mentioned. thanks you for the replies.

6

Libraries are usually applicable to boards with the same chips.

7

One thing beginners often miss is that the chips need decoupling capacitors to work reliably. If these sensors are on some sort of PCB then the decoupling might be included but sometimes it is missed out for the sake of saving cost.

However, some of the cheaper sensors, while not being clones, might be chips from the reject bin of legitimate chips being manufactured. Not actually broken but not meeting the full specification in some way.